How does the Venus has some kind of rain when the inside temperature is so hot that evaporates everything? There is nothing that can cool the atmosphere to make some rain?

Rodolfo

There is no sulfuric acid rain on the surface of Venus. There has been speculation that it exists in the upper levels of the atmosphere. But in none of those models does it come anywhere near the surface before evaporating.

There is no sulfuric acid rain on the surface of Venus. There has been speculation that it exists in the upper levels of the atmosphere. But in none of those models does it come anywhere near the surface before evaporating.

...So, after verifying that there is also a 2-pixel shift visible on Venera 13 camera #2 images (between clear pans 1 and 2), I decided to apply my techniques building an hi-res Venera 13 color image from the data available.

I then built 2 different pancromatic pans : the 1st one from clear pan 1 (filling the gaps with green pan 1 and red 1 pan) and the 2nd one from clear pan 2 (filling the gaps with green pan 2 and red pan 2). Then I pixel-overlapped them to build an hi-res pancromatic pan. This one was then fused with the colors of the low-res picture (shown on item #1 : http://www.unmannedspaceflight.com/index.p...dpost&p=20445);

Here is the result : a gain of a 1.3-1.5 resolution over my previous color version.I think it shows the maximum of details I can retrieve now from the V13 data.Enjoy !

Absolutely breathtaking! I'm amazed at the caliber of science that is represented on this site. You are all doing a tremendous service to all mankind by transcending international borders in your work. I'm honored and thrilled to be part of this forum!

There is no sulfuric acid rain on the surface of Venus. There has been speculation that it exists in the upper levels of the atmosphere. But in none of those models does it come anywhere near the surface before evaporating.

It's more than "speculation"; it's been known fact for three decades. Venus' clouds are a mist of sulfuric acid, produced by the fact that the traces of sulfur dioxide dumped into its air by its still-actve volcanoes rise high into the atmosphere and are converted by solar UV into sulfur trioxide, which in turn reacts very readily with the remaining tracres of water vapor to form an H2SO4 cloud layer at the 64 to 46 km level. (This is the same process that created such large amounts of H2SO4 on early Mars, which as we now know has had a radical effect on its surface mineralogy.)

But:

(1) As one might expect, given the tiny trace amounts of the gases out of which they form, Venus' clouds are actually very rarified -- you could see through them for kilometers with little blurring. They are opaque to visible light as seen from above (or below) simply because the layer is so spatially thick (as is also the case with Titan's organic smog).

(2) Pioneer 13's biggest entry probe carried a cloud particle-size spectrometer which worked fine -- but detected not a single, solitary particle in Venus' air from 30 km altitude down to the surface.

(3) There are obviously other substances mixed in with the H2SO4 in Venus' clouds, whose identifies we do not know well, and which are subjects of major scientific interest. In particular, there's the stuff that makes so many regions of Venus' clouds look dark in UV photos -- we actually still do not know what this UV absorber is, although the favored theories revolve around its being one of several sulfur compounds. Then there's the possible detection by several of the Soviet landers of small amounts of other elements (Cl, P, and I think Fe) in the clouds, although given the accuracy of Soviet science instruments this is open to question. Finally, that same cloud particle-size spectrometer on Pioneer 13 located what seems to be a small separate population of cloud particles which are considerably larger than the other liquid acid droplets -- and may possibly be nonspherical solid crystals of something.

(Thanks to all for your great contributions about atmospheric science !)

...and (following post 35), I decided to make an acknowledgement to the fantastic art work of Don Davis, by quickly correcting the perspective of the Venera 13 panorama, following his "Venera Grid" made in 1987.Here is the Venera 13 "Daviscape" ! Enjoy !

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